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polypyrrole
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Polypyrrole nanowires network for convenient and highly efficient microextraction in packed syringe
, Article Analytical Methods ; Volume 3, Issue 11 , 2011 , Pages 2630-2636 ; 17599660 (ISSN) ; Ayazi, Z ; Sharif University of Technology
Abstract
A novel method based on microextraction in packed syringe (MEPS), as a sample preparation technique in combination with gas chromatography-mass spectrometry (GC-MS) was developed using a polypyrrole (PPy) nanowires network as the extracting medium. The PPy nanowires network was prepared using a soft template technique and its characterization was studied by scanning electron microscopy (SEM). The use of micelles in this methodology has an important role in the shape of the growing polymer. The pyrrole monomer was introduced into cetyltrimethylammonium bromide (CTAB) micelles and this has led to the formation of nanowires with diameters ranging from 30 to 60 nm. The bulk PPy prepared without...
Electrochemical preparation of a molecularly imprinted polypyrrole modified pencil graphite electrode for the determination of phenothiazine in model and real biological samples
, Article Talanta ; Volume 144 , November , 2015 , Pages 456-465 ; 00399140 (ISSN) ; Rouki, Z ; Nezhadali, M ; Sharif University of Technology
Elsevier
2015
Abstract
Abstract A sensitive electrochemical sensor for determination of phenothiazine (PTZ) was introduced based on molecularly imprinted polymer (MIP) film. A computational study was performed to evaluate the template-monomer geometry and interaction energy in the prepolymerization mixture. The electrode was prepared during electropolymerization of pyrrole (Py) on a pencil graphite electrode (PGE) by cyclic voltammetry (CV) technique. The quantitative measurements were performed using differential pulse voltammetry (DPV) in Britton-Robinson (BR) buffer solutions using 60% (v/v) acetonitrile-water (ACN/H2 O) binary solvent. The effect of important parameters like pH, monomer...
Investigation of the electrochemical behavior of tizanidine on the surface of glassy carbon electrode modified with multi-walled carbon nanotube/titan yellow–doped polypyrrole
, Article Journal of Electroanalytical Chemistry ; Volume 823 , 2018 , Pages 146-154 ; 15726657 (ISSN) ; Shamloofard, M ; Salimian, R ; Sharif University of Technology
Abstract
The present paper describes a voltammetric sensor based on glassy carbon electrode (GCE) modified with a thin film of multi-walled carbon nanotubes (MWCNTs) coated with an electro-polymerized layer of titan yellow-doped over–oxidized polypyrrole (OPPY) for the determination of tizanidine (TIZ). A significant enhancement was observed in the anodic peak current of TIZ on the surface of OPPY/CNT/GCE, relative to the bare, CNT- and OPPY-coated GCEs. The microscopic structure and surface morphology of the composite film was thoroughly characterized by means of atomic force microscopy (AFM), scanning electron microscopy (SEM) and cyclic voltammetry (CV) techniques. The effect of various...
Ternary nanostructures of Cr2O3/graphene oxide/conducting polymers for supercapacitor application
, Article Journal of Electroanalytical Chemistry ; Volume 823 , 2018 , Pages 505-516 ; 15726657 (ISSN) ; Shahrokhian, S ; Iraji Zad, A ; Sharif University of Technology
Abstract
In this work, nanostructured composites of Cr2O3-graphene oxide (Cr2O3/GO) with conducting polymers; polyaniline (PANI) and polypyrrole (PPy) with the shape of cauliflower were synthesized via s simple and low cost one-step chronoamperometry method. The structures and morphologies of the resulting ternary nanocomposites were characterized by using Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The electrochemical capacitive properties of the prepared nanocomposites were evaluated by using cycle voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy. The...
Efficient single and bi-layer absorbers of CaTiO3 micro-cubes and polypyrrole nanotubes composites for enhanced microwave absorption in X and Ku band
, Article Ceramics International ; Volume 48, Issue 9 , 2022 , Pages 11953-11961 ; 02728842 (ISSN) ; Abdelbasset, W. K ; Elkholi, S. M ; Ismail, K. A ; Akhtar, M. N ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
The present study is focused on the investigation of the absorption properties of the bi-layer absorber with different thickness and orientation approaches. Improvement in absorption exclusively depends on the various parameters as interfacial polarization, multiple reflections among layers, conduction loss, phase cancellations, and shape anisotropy, etc. By considering these parameters. Calcium titanate micro-cubes CaTiO3 (CTO) and polypyrrole nanotubes (PPy) nanocomposites were prepared and microwave absorption from single layer coaxial absorbers having M1 = CaTiO3+15 wt% polymer and M2 = CaTiO3+30 wt% polymer were determined. Different layer orientations and thicknesses of the bi-layer...
Development and Application of Carbon Nanomaterials-based Polymer Modified Electrodes for Electrochemical Determination of Pharmaceutical Compounds
, Ph.D. Dissertation Sharif University of Technology ; Shahrokhian, Saeed (Supervisor)
Abstract
In this thesis, in the first part, a promising electrochemical sensor was developed based on a layer by layer process by electropolymerization of pyrrole in the presence of new coccine (NC) as dopant anion on the surface of the CNTs pre-coated glassy carbon electrode (GCE). The modified electrode was used as a new and sensitive electrochemical sensor for voltammetric determination of sumatriptan (SUM). The results showed a remarkable increase in the anodic peak current of SUM in comparison to the bare GCE. In the second part, the electropolymerization of pyrrole was performed in the presence of Nitrazine Yellow (NY) as a dopant anion on the surface of the electrode precoated with CNTs. The...
Preparation and Investigation of Electrochemical Sensors for Determination of Pharmaceutical and Biological Compunds Based on Glassy Carbon Electrode Modified with Polypyrrole/Carbon Nanotube Composite
, M.Sc. Thesis Sharif University of Technology ; Shahrokhian, Saeed (Supervisor)
Abstract
In the recent years, conductive polymers are widely used in the design and construction of chemical and biological sensors.The polypyrrole due to features such as good thermal and chemical stability, ease of synthesis and better conductivity than other conductive polymers, atracts much attention. In order to modification of electrode surface,adhesiveand thin polymer films can be electropolymerized in the presence of organic or inorganic dopants on the surface of metal or carbon surfaces in aqueous or organic solutions. On the other hand carbon nanotubes by owing unique properties such as chemical stability and high electrical conductivity are good choice for electrod surface modification....
An Interior Needle Trap by Electropolymerized Pyrrole-based Coating for Headspace Solid-Phase Dynamic Extraction of Chlorobenzenes and Their Determination with Gas Chromatography-Mass Spectrometry
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
Chlorinated benzenes are a group of cyclic aromatic compounds which are used mainly as intermediates in the synthesis of pesticides and other chemicals. These compounds have harmful effects on human health, as on blood, kidneys, skin and eyes, and cause biological disorders and cancers. Chlorobenzenes have been ranked as priority pollutants by the US Environmental Protection Agency (EPA). The permissible level of these compounds for drinking water ranges between 2 μg/L and 1 mg/L. Hence determination of these compounds is of a significant importance. Solid Phase Dynamic Extraction (SPDE) of 5 types of chlorobenzenes (monochlorobenzene, 1,4-dichlorobenzene, 1,2,3-trichlorobenzene,...
Constructing and Investigation of the Electrochemical Behavior of Nanocomposite of Conducting Polymers on Copper Hydroxide Nanotubes; Application to Determination of Glucose
, M.Sc. Thesis Sharif University of Technology ; Shahrokhian, Saeed (Supervisor)
Abstract
A novel amperometric non-enzymatic glucose (NEG) sensor is designed by a facile preparation method. It is made by electrodeposition of Cu clusters and converting them to Cu(OH)2 nanotubes (Cu(OH)2NTs) arrays along with thin-film electro-polymerized of spindle-shaped polypyrrole (PPy@Cu(OH)2NTs), which have been doped by using sodium Benzene-1,3- disulfonate as an anion dopant. The electrochemical performance of the modified electrode toward glucose detection is investigated by various electrochemical methods. Under the optimized conditions, a significant electrochemical response improvement is observed toward the electro-oxidation of glucose on the surface of PPy@Cu(OH)2NTs electrode...
Synthesis and Characterization of CuO Microflowers/Ppy Nanowires NCs as Anode Materials for Lithium-ion Battery
, M.Sc. Thesis Sharif University of Technology ; Sadrnezhad, Khatiboleslam (Supervisor)
Abstract
Novel Copper Oxide microflowers /Polypyrroles nanowire nanocomposites with various wight ratio have been synthesized.The synthesized CuO/Ppy NCs and Cuo microflowers are characterized by XRD, FT-IR, TGA, FESEM and EDX line analysis/elemntal mapping. The formation mechanism of CuO microflower and Ppy nanowires are also well explained.All syntesized samples have been used as as anode material for li-ion batteries in order to measure their electochemical lithium-ion storage properties. It is demonstrated that presence of Ppy nanowire with different weight ratio plays important role in lithium-storage properties of the hybrid CuO/Ppy NCs. With increase in the mass ratio of Ppy nanowire cyclic...
Development of Nanostructured Lithium-Rich Cathode Material
, Ph.D. Dissertation Sharif University of Technology ; Sadrnezhaad, Khatiboleslam (Supervisor)
Abstract
This research is divided in three parts. In the first part of this research, we report the one-pot synthesis of carbonate-coated nanostructured LLO (Li2CO3@LLO) through a polyol-assisted method as a Li-ion battery cathode. Carbonate protects the cathode from adverse reactions with the electrolyte, also reduces the layered-to-spinel phase transition, thereby stabilizing the cathode structure. LLO nanostructure provides a fast Li+ diffusion. The target material exhibits excellent long-term stability with 77% capacity retention after 1000 cycles at 0.2C-rate. In the second part of research, Li(Na-doped)-Mn-Ni-O oxides were synthesized by different LiOH.H2O amount, type and amount of reducing...
A chitosan-polypyrrole magnetic nanocomposite as μ-sorbent for isolation of naproxen
, Article Analytica Chimica Acta ; Vol. 816 , 2014 , Pages 1-7 ; ISSN: 00032670 ; Roostaie, A ; Baktash, M. Y ; Sharif University of Technology
Abstract
An extracting medium based on chitosan-polypyrrole (CS-PPy) magnetic nanocomposite was synthesized by chemical polymerization of pyrrole at the presence of chitosan magnetic nanoparticles (CS-MNPs) for micro-solid phase extraction. In this work, magnetic nanoparticles, the modified CS-MNPs and different types of CS-PPy magnetic nanocomposites were synthesized. Extraction efficiency of the CS-PPy magnetic nanocomposite was compared with the CS-MNPs and Fe3O4 nanoparticles for the determination of naproxen in aqueous samples, via quantification by spectrofluorimetry. The scanning electron microscopy images obtained from all the prepared nanocomposites revealed that the CS-PPy magnetic...
Design, fabrication, and characterization of novel porous conductive scaffolds for nerve tissue engineering
, Article International Journal of Polymeric Materials and Polymeric Biomaterials ; Volume 64, Issue 18 , 2015 , Pages 969-977 ; 00914037 (ISSN) ; Ahmad Ramazani, S. A ; Mashayekhan, S ; Farani, M. R ; Ghaderinezhad, F ; Dabaghi, M ; Sharif University of Technology
Taylor and Francis Inc
2015
Abstract
Highly conductive polypyrrole/graphene (PYG) nanocomposite was synthesized with chemical oxidation process via emulsion polymerization and used for the preparation of novel porous conductive gelatin/chitosan-based scaffolds. The effect of PYG loading on various properties of scaffolds was investigated. The obtained results indicated that by introducing PYG into the polymeric matrix, the porosity and swelling capacity decreased while electrical conductivity and Young's modulus demonstrated increasing trend. The in vitro biodegradation test revealed that pure gelatin/chitosan matrix lost 80% of its weight after six weeks in the presence of lysozyme whilst the biodegradation rate was...
An Fe3O4@SiO2@polypyrrole magnetic nanocomposite for the extraction and preconcentration of Cd(ii) and Ni(ii)
, Article Analytical Methods ; Volume 7, Issue 1 , Nov , 2015 , Pages 313-320 ; 17599660 (ISSN) ; Hosseinzadeh Khanmiri, R ; Ghorbani Kalhor, E ; Hassanpour, A ; Asgharinezhad, A. A ; Shekari, N ; Fathi, A ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
This work describes a novel Fe3O4@SiO2@polypyrrole magnetic nanocomposite and its application in the preconcentration of Cd(ii) and Ni(ii) ions. The parameters affecting the preconcentration procedure were optimised by a Box-Behnken design using response surface methodology. Three variables (extraction time, magnetic sorbent amount, and pH) were selected as the main factors affecting the sorption step, while four variables (type, volume and concentration of the eluent, and elution time) were selected as the main factors in the optimisation study of the elution step. Following the sorption and elution of analytes, the ions were quantified by FAAS. The limits of detection were 0.3 and 1.2 ng...
Construction of a ternary nanocomposite, polypyrrole/fe-co sulfide-reduced graphene oxide/nickel foam, as a novel binder-free electrode for high-performance asymmetric supercapacitors
, Article Journal of Physical Chemistry C ; Volume 124, Issue 8 , 2020 , Pages 4393-4407 ; Kazeminezhad, I ; Naderi, L ; Shahrokhian, S ; Sharif University of Technology
American Chemical Society
2020
Abstract
The development of asymmetric supercapacitors requires the design of electrode construction and the utilization of new electroactive materials. In this regard, an effective strategy is the loading of active materials on an integrated 3D porous graphene-based substrate such as graphene foam (GF). Herein, we successfully designed and fabricated a novel ternary binder-free nanocomposite consisting of polypyrrole, Fe-Co sulfide, and reduced graphene oxide on a nickel foam electrode (PPy/FeCoS-rGO/NF) via a facile, cost-effective, and powerful electrodeposition method for application in high-performance asymmetric supercapacitors. The monolithic 3D porous graphene foam (GF) obtained by the facile...
One step electrodeposition of V2O5/polypyrrole/graphene oxide ternary nanocomposite for preparation of a high performance supercapacitor
, Article International Journal of Hydrogen Energy ; Volume 42, Issue 33 , 2017 , Pages 21073-21085 ; 03603199 (ISSN) ; Shahrokhian, S ; Iraji zad, A ; Sharif University of Technology
Abstract
A new ternary nanocomposite based on graphene oxide (GO), polypyrrole (PPy) and vanadium pentoxide (V2O5) is obtained via one-step electrochemical deposition process. Electrochemical deposition of V2O5, PPy and GO on a stainless steel (SS) substrate is conducted from an aqueous solution containing vanadyl acetate, pyrrole and GO to get V2O5/PPy/GO nanocomposite. Characterization of the electrode material is carried out by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and atomic force microscopy (AFM). The electrochemical performance of the as-prepared nanocomposite is evaluated by...
Electrochemical determination of clozapine on MWCNTs/new coccine doped ppy modified GCE: An experimental design approach
, Article Bioelectrochemistry ; Volume 90 , 2013 , Pages 36-43 ; 15675394 (ISSN) ; Kamalzadeh, Z ; Hamzehloei, A ; Sharif University of Technology
2013
Abstract
The electrooxidation of clozapine (CLZ) was studied on the surface of a glassy carbon electrode (GCE) modified with a thin film of multiwalled carbon nanotubes (MWCNTs)/new coccine (NC) doped polypyrrole (PPY) by using linear sweep voltammetry (LSV). The pH of the supporting electrolyte (D), drop size of the cast MWCNTs suspension (E) and accumulation time of CLZ on the surface of modified electrode (F) was considered as effective experimental factors and the oxidation peak current of CLZ was selected as the response. By using factorial-based response-surface methodology, the optimum values of factors were obtained as 5.44, 10 μL and 300 s for D, E and F respectively. Under the optimized...
Polypyrrole/polyamide electrospun-based sorbent for microextraction in packed syringe of organophosphorous pesticides from aquatic samples
, Article Journal of Separation Science ; Volume 35, Issue 1 , December , 2012 , Pages 114-120 ; 16159306 (ISSN) ; Ayazi, Z ; Aghakhani, A ; Alipour, N ; Sharif University of Technology
Abstract
A novel method based on microextraction in packed syringe (MEPS) as sample preparation technique coupled off-line with gas chromatography-mass spectrometry was developed using electrospun nanofibers as sorbent. For electrospinning of polypyrrole/polyamide-based nanofiber, a homogeneous solution containing nylon 6, ferric chloride and pyrrole monomer was prepared and then was drawn into a 2.5-mL syringe. By applying a voltage of 13akV between the needle of the syringe and an aluminum-foil collector, the nanofibers could be formed on the surface of the collector. The prepared sheet was used as the sorbent for MEPS to analyze some selected organophosphorous pesticides. Important parameters...
Electrochemical preparation of over-oxidized polypyrrole/multi-walled carbon nanotube composite on glassy carbon electrode and its application in epinephrine determination
, Article Electrochimica Acta ; Volume 57, Issue 1 , 2011 , Pages 132-138 ; 00134686 (ISSN) ; Saberi, R. S ; Sharif University of Technology
Abstract
A composite film constructed of surfactant doped over-oxidized polypyrrole and multi-walled carbon nanotube was prepared on the surface of glassy carbon electrode by the electro-polymerization method. Surface characterization of the modified electrode was performed by scanning electron microscopy, cyclic voltammetry and electrochemical impedance spectrometry. The investigations have been proved that the over-oxidation of the modifier film resulted in a porous thin layer that improves the interlayer diffusion mechanism for the electroactive species. On the other hand, the negative charge density on the surface of the electrode excludes the negative analytes (e.g. ascorbate and Fe(CN)63?/4?)...
Modification of glassy carbon electrode with a bilayer of multiwalled carbon nanotube/tiron-doped polypyrrole: Application to sensitive voltammetric determination of acyclovir
, Article Materials Science and Engineering C ; Volume 53 , 2015 , Pages 134-141 ; 09284931 (ISSN) ; Azimzadeh, M ; Amini, M. K ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
A novel voltammetric sensor based on glassy carbon electrode (GCE) modified with a thin film of multi-walled carbon nanotubes (MWCNTs) coated with an electropolymerized layer of tiron-doped polypyrrole was developed and the resulting electrode was applied for the determination of acyclovir (ACV). The surface morphology and property of the modified electrode were characterized by field emission scanning electron microscopy and electrochemical impedance spectroscopy techniques. The electrochemical performance of the modified electrode was investigated by means of linear sweep voltammetry (LSV). The effect of several experimental variables, such as pH of the supporting electrolyte, drop size of...